Fomrhi Comm. 2056 Jan Bouterse Making Woodwind Instruments 6A- the Lathe There Are People Who Are Afraid of Lathes: Turning Piec
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FoMRHI Comm. 2056 Jan Bouterse Making woodwind instruments 6a- The lathe There are people who are afraid of lathes: turning pieces of wood on such an engine is for them such unknown territory that they prefer other methods to make their instrument parts round. And that is, of course, possible. With sharp hand tools (even with a pocket knife - I prefer Swiss army knives of the brand Victorinox) you can cut any piece of wood into a profile which is perfectly round in cross section. For simple instruments without elaborate baroque profiles, for instance small fifes made of branches of elder wood (where the central bore is drilled through the heart of the branch), this way of working is a good exercise, you can do it on a quiet walk through the forests. And instruments such as a dulcian or bassoon must also be shaped using planes and chisels (and/or a lot of sand paper): most of their parts have no circular cross section and cannot - apart from some sections - be turned on a lathe. The other way to avoid turning, is making square instruments. Herbert Paetzold in Ger- many was a pioneer in designing very fine bass (and longer) recorders. These instruments have the advantage that they can be played with quite simple wooden keys which can also easily be mounted on the flat surface of the wood. Some members of the Bouwerskontakt have recently made long square recorders; they discovered that it is very important - but also quite difficult to achieve - to get the connections between the parts of the instruments perfectly airtight. It is also important to use the best quality of laminated wood, without any gaps between the layers. My question: why do I not see square versions or other long wood- wind instruments, such as dulcians of bassoons - apart from some experiments by Daniel Bangham which I saw last year on the Galpin Conference in Cambridge? Here is a square soprano recorder, after a design by Alec Loretto. I cut the windway in a piece of wood which can easily be removed by loosening the screws (just as the block which is screwed on from the back side). An electric drill as drive for your lathe Another reason to avoid a lathe is that the machine takes some space in your house or shed. And apart from turning, drilling or polishing wood (or some other materials like ivory substitutes), you can’t use a lathe for many other things. When in 1980 I had the plan to make a recorder, I didn’t yet know whether that was the beginning of a serious hobby or even a profession, or only a shortlived experiment. I also had not much money to spend, so I bought a set of lathe accessories for my electric drill. This set was by AEG and I made some fine instruments on it before I bought a bigger and more versatile ‘real’ lathe. More recently I bought a similar lathe set to use with a power drill by Wolfcraft (photo below), because I needed for my work- shops an easy transportable lathe. Both lathe set-ups by AEG and Wolfcraft are now out of production (and I sold mine), but maybe you can find them second-hand. The advantage of this type of lathe equipment is that you can easily make the working distance as long as you want. Stability might then become a problem, but - for instance - turning a long thin- walled renaissance flute on a heavy professional lathe is also awkward. Another point to remember is that the bearings of electric drills are designed to be sturdy for drilling. But used on a lathe, the machine is exposed to forces perpendicular to the axis, which might cause problems. That’s probably the reason that Wolfcraft designed on its lathe a connecting piece between the chuck of the drill and the spur centre. I must mention two further problems: an electric drill is noisy and you must not use it in the same horizontal position for a longer time. For safety reasons it is also better to make an extra on/off switch. within easy reach of hands, or feet. Here is a TRT MC600 Drill powered woodturning lathe by Axminster, for about 60 English pounds (the power drill is not included in the set) a cheap alternative for the man who doesn’t want to spend too much money on his hobby. It does not have, like the Wolfcraft, a connecting piece from the drill chuck and the spur centre (or - as on the photo - a face plate). But is the Axminster set good, and pleasant to use, and is it worth the money? On the website of Axminster you can see some surprisingly negative reviews, and the more positive ones mention problems with for instance the tightening of the screws. I think that the Wolfcraft is (or was) better, for instance having a much more stable tailstock spindle. Maybe you can improve some parts of the Axminster set, but that is then the start of making a complete new lathe of your own design. I have known some people who did that, using a motor from a washing machine and some bike parts for the bearings. But for some parts of such a lathe you need another lathe to make them, which might be troublesome. The pole lathe There is another way to make a special type of lathe, the historical pole lathe. This has no motor, but instead you use one of your legs - it is also fitness training! I found this information on Wikipedia: A pole lathe is a wood-turning lathe that uses a long pole as a return spring for a treadle. Pressing the treadle with your foot pulls on a cord that is wrapped around the piece of wood or billet being turned. The other end of the cord reaches up to the end of a long springy pole. As the action is reciprocating, the work rotates in one direction and then back the other way. Cutting is only carried out on the down stroke of the treadle, the spring of the pole only being sufficient to return the treadle to the raised position ready for the next down stroke. The Wikipedia author also says that a requirement is that the timber used on a pole lathe is freshly felled and unseasoned, i.e., green. I do not agree; most woodwind instruments from baroque and earlier periods were made of really hard and well seasoned woods, and on pole lathes. He is possibly correct with another statement: The angle that the tools are ground is closer to that of a carpenter's chisel than that of a power lathe tool. Using power lathe tools on a pole lathe is safe, but hard work. Using a pole lathe chisel on a power lathe risks serious injury, since the forces are such that the blade is likely to break. I have seen two beautiful pole lathes in the recorder factory of Mollenhauer in Fulda (Germany, see photo left). School classes can here learn how to turn wood in a safe way. The spring action comes cleverly from two verti- cal poles, attached to both sides of the lathe. The construction is clearly visible on the pictures, also the way that the wood is mounted between the centres of the lathe. It seems to me a perfect project for any school to make this type of pole lathe from scratch and then to use it for making finely turned products. Pole lathes have some advantages over power lathes. One of them is the much lower speed of the turning. And that gives, together with the reciprocating action, the possibility of turning screw threads. There is a picture of a lathe of a maker of musical instruments in the famous Encylopédie ou dictionnaire raisonné des sciences, des arts et des métiers by Diderot and d’Alembert and published between 1751 and 1772, with later supplements. This picture (see below) needs some explanation: the rope is wrapped around an arbor and not around the workpiece (which hat to be mounted into a mandrel which is attached to the screw, G on the picture). The arbor has no fixed position, but can shift sideways over some distance. The arbor has at its left side a series of various types of threads, but putting a slide (in box B) into one of the threads, the desired shift will be realized and the thread will be reproduced by simply using the right tool (fig. 15 and 16 on the picture), pushing that against the turning and shifting wood. The movable arbor of the lathe (fig 8.) and the mandrel (fig. 4), for mounting round objects. In Comm. 2053 I wrote about ornamental turning of ivory; more elaborate templates were used to get the desired ornaments. Cecil Adkins wrote about how ornamental lathes were brought to perfection by the development of the treadle lathe in the 17th century. This type of lathe has a continuous motion and when provided with a flywheel you can work more efficiently. On the site woodworkers-online.com/2011/02/easy-to-build-continuous- motion-treadle. html you can find inspiration and technical tips on how to make a treadle lathe yourself. I have seen several old treadle lathes in local museums. On this photo (Erlenbach, Switzer- land) is the flywheel placed at the left side of the lathe. It looks all rather primitive, but it is in working order an you can make the finest workpieces on it! Modern wood lathes The ideal wood lathe is versatile, stable, with sufficient length between the centres, easy to clean, safe to use and not too expensive.